This invention relates to a magnetic recording medium, a method of producing the same and a magnetic recording apparatus using the same, and particularly to ones in which the lubricant coated on the surface of the medium can be effectively prevented from being scattered and the shearing force caused when the magnetic head is made in contact with the medium can be reduced by the lubricant so that the protective film can be prevented from being worn away.
The general magnetic disk recording apparatus records information on the magnetic recording medium in the form of a great number of concentric circulars or spiral tracks. In this case, in order to improve the recording density, it becomes necessary to increase the circumferential information density (linear recording density) along the tracks. The linear recording density depends on the characteristics (coercive force, film thickness and so on) of the magnetic film of the magnetic recording medium the characteristics (frequency characteristics, gap length and so on) of the magnetic head and the spacing between the magnetic film of the medium and the magnetic head.
In recent years, the spacing (hereinafter, called flying height of floating) between the magnetic head and the magnetic recording medium when the head is driven has shown a rapid change to usually as narrow as 0.1 through 0.2 .mu.m. In addition, as described in the Proceedings of the First International Workshop on Microtribology Oct. 12-13, 1992, pp. 192-199, the flying height of floating of the magnetic head is 0, and as a result upon recording or reproduction the magnetic head is made contact with the surface of the magnetic recording medium in a certain magnetic disk recording apparatus.
Moreover, although a lubricant has so far been coated on the surface of the protective film of the medium, the lubricant coated on the film has recently often been a polar group as disclosed in JP-A-4-125813.
In the general magnetic disk recording apparatus, when the flying height of floating is extremely small, or when the magnetic head is made nearly in contact or directly in contact with the magnetic medium, the medium is worn away by contacting with the magnetic head so that a destruction or the like, called crush, sometimes occurs to prevent the data on the medium from being reproduced therefrom.
It is necessary not to make the head contact with the surface of the medium in order that this crush can be avoided, but in practice dust and gas intervene and can cause the head to come in contact with the medium. In addition, the magnetic disk recording apparatus in which the magnetic head is made to contact the magnetic recording medium is naturally required to consider the contact therebetween as disclosed in the Proceedings of the First International Workshop on Microtribology Oct. 12-13, 1992, pp. 192-199.